Mobile terminal and control method thereof

ABSTRACT

There is provided a mobile terminal capable of being protected against unauthorized use by a third party without using a dedicated key device. A plurality of mobile terminals are previously registered mutually. When unlocked among them, one mobile terminal communicates with another mobile terminal in a communication range of short-range wireless communications, unlocks the above another mobile terminal, and when out of the communication range, locks it again.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.13/874,535 filed May 1, 2013 and entitled “MOBILE TERMINAL AND CONTROLMETHOD THEREOF,” which is related to and claims priority from JapaneseApplication No. JP2012-117105 filed May 23, 2012, each of which isincorporated herein by reference in its entirety and from each of whichpriority is claimed.

BACKGROUND OF THE INVENTION

The present invention relates to a mobile terminal and a control methodthereof.

As a background art of this technical field, JP-A-2004-102682 isdisclosed. In its publication, a problem will be described as below.“According to the conventional schemes described above, therefore, theuser of the terminal device needs to make a complex action in order toprevent a third party from making unauthorized use of the terminaldevice. If the user has inadvertently made the password known or lostthe terminal device together with the ID card, then it is impossible toreliably prevent unauthorized use of the terminal device by a thirdparty.”

A method for solving this problem will be described as below. “There isprovided a terminal lock system for verifying that the user of aterminal device is a person with the legitimate right to use theterminal device for thereby protecting the terminal device againstunauthorized use by a third party, the terminal lock system comprising akey device and a terminal-associated device. The key device is portableand has a radio communication means for performing short-range wirelesscommunications. The terminal-associated device requests a connection tothe key device through the short-range wireless communications, andinhibits the terminal device which is combined with theterminal-associated device from being used if information of the keydevice which is confirmed as being connected to the terminal-associateddevice does not agree with information registered in theterminal-associated device, or if the terminal-associated device is notconfirmed as being connected to the key device through the short-rangewireless communications.”

SUMMARY OF THE INVENTION

In JP-A-2004-102682, the following advantage will be described. “Withthe above arrangement, when the user who is carrying the key devicemoves away from the terminal device combined with theterminal-associated device until the terminal-associated device and thekey device are no longer capable of connecting to each other based on ashort-range wireless communication technique, the terminal-associateddevice locks the terminal device against use. The terminal lock systemthus authenticates the user without the need for asking the user to makeany action, and reliably protects the terminal device againstunauthorized use by a third party.”

However, the user needs to always carry the dedicated key device havinga communication function when using the terminal device.

In view of the foregoing, it is an object of the present invention toprovide a convenient mobile terminal and control method thereof capableof being protected against unauthorized use by a third party withoutusing the dedicated key device.

The object of the present invention can be attained by the followingtechnical proposal: For example, a plurality of mobile terminals arepreviously registered mutually. When unlocked among them, one mobileterminal communicates with another mobile terminal in a communicationrange of the short-range wireless communications, unlocks the aboveanother mobile terminal, and when out of the communication range, locksit again.

According to the present invention, for example, when one mobileterminal is unlocked among a plurality of mobile terminals, anothermobile terminal can be unlocked.

Other objects, features and advantages of the invention will becomeapparent from the following description of the embodiments of theinvention taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram illustrating a configuration of a mobileterminal according to a first embodiment;

FIG. 2 is a flowchart illustrating operations for locking and releasinga mobile terminal 1 according to a first embodiment;

FIG. 3 is a flowchart illustrating operations for locking and releasinga mobile terminal 2 according to a first embodiment;

FIG. 4 is a flowchart illustrating operations for locking and releasinga mobile terminal 1 according to a second embodiment;

FIG. 5 is a flowchart illustrating operations for locking and releasinga mobile terminal 2 according to a second embodiment;

FIG. 6 is a flowchart illustrating operations for locking and releasinga mobile terminal 1 according to a third embodiment;

FIG. 7 is a display example illustrating a liquid crystal panel of amobile terminal according to a third embodiment;

FIG. 8 is a flowchart illustrating operations for locking and releasinga mobile terminal 1 according to a fourth embodiment;

FIG. 9 is a flowchart illustrating operations for locking and releasinga mobile terminal 1 according to a fifth embodiment; and

FIG. 10 is a flowchart illustrating a warning operation of a mobileterminal 1 according to a sixth embodiment.

DESCRIPTION OF THE EMBODIMENTS

Hereinafter, preferred embodiments of the present invention will bedescribed with reference to the accompanying drawings of theembodiments.

First Embodiment

FIG. 1 is a block diagram illustrating a configuration of a mobileterminal according to a first embodiment of the present invention. Themobile terminals 1 and 2 each have a radio communication function, andtransmit and receive a variety of information to and from a mobile basestation 3. Further, the mobile terminals 1 and 2 each have a function ofperforming short-range wireless communication between mobile terminals,and can transmit and receive a variety of information between the mobileterminals 1 and 2 by using the function. Examples of the short-rangewireless communication include Bluetooth (trademark), infrared rays, andWi-Fi Direct.

A controller 11 controls each unit of the mobile terminal 1. Thecontroller 11 is configured by a CPU (Central Processing Unit), anarbitrary control circuit, or a dedicated circuit such as an ASIC.

A display unit 12 of the mobile terminal 1 is configured, for example,by a liquid crystal panel, and displays a variety of information. Anoperating unit 13 is configured, for example, by a push-button switch ora touch panel, and an instruction of a user is transferred to thecontroller 11. A wireless communications unit 15 and a short-rangewireless communication unit 16 are each configured by a communicationcircuit including an encoding circuit and a decoding circuit in additionto an antenna. The wireless communications unit 15 communicates with themobile base station 3. The short-range wireless communication unit 16controls short-range wireless communications and communicates, forexample, with the mobile terminal 2.

A storage unit 14 stores a program or various kinds of settinginformation for controlling a mobile terminal, and a password forunlocking a mobile terminal.

A controller 21, a display unit 22, an operating unit 23, a storage unit24, and a wireless communications unit 25 of the mobile terminal 2 arethe same as the controller 11, the display unit 12, the operating unit13, the storage unit 14, and the wireless communications unit 15 of themobile terminal 1, and therefore, descriptions will not be repeatedhere. A short-range wireless communication unit 26 controls short-rangewireless communications, and communicates, for example, with the mobileterminal 1.

Next, descriptions will be made about operations which are set until themobile terminal 2 is unlocked after the mobile terminal 1 is unlocked.

In addition, the locked state of the present embodiment is a state inwhich functions or operations of part or the whole of a mobile terminalare limited.

When the user refers to the display unit 12 of the mobile terminal 1 andoperates the operating unit 13 so as to release a locked state, themobile terminal 1 searches whether another mobile terminal is in ashort-distance communication range capable of performing short- rangewireless communications. The mobile terminal 1 further confirms whetherit is the mobile terminal 2 being a previously registered mobileterminal. When the mobile terminal 1 confirms that information stored inthe storage unit 14 is matched with that of the storage unit 24 and itis the previously registered mobile terminal, the mobile terminal 2 isunlocked.

The mobile terminals 1 and 2 are supposed to transit to a locked statewhen not operated for a given length of time and, for example, apassword is supposed to need to be entered in order to release thelocked state. The given length of time is, for example, thirty seconds.Further, the mobile terminals 1 and 2 are previously registered so as tobe mutually locked and unlocked through short-range wirelesscommunications.

An example where the mobile terminals 1 and 2 each have a radiocommunication function with the mobile base station 3 is illustrated.Further, the mobile terminal 1 and/or mobile terminal 2 may each have awireless LAN (Local Area Network) function, and transmit and receive avariety of information to and from a wireless LAN router.

FIG. 2 is a flowchart illustrating operations of locking and unlockingthe mobile terminal 1 according to the first embodiment.

First, at step S201, the mobile terminal 1 confirms whether to beunlocked when the user enters a password. The mobile terminal 1continues to wait for unlocking until the locked state is released, andwhen it is unlocked, the process proceeds to step S202. An example wherethe user enters a password is described here, and biometricsauthentication may be further used.

At step S202, the mobile terminal 1 searches mobile terminals in theneighborhood through short-range wireless communications. For example,the mobile terminal 1 transmits radio waves used for the short-rangewireless communications and searches for a mobile terminal in which theshort-range wireless communications are established by receiving theradio waves.

At step S203, the mobile terminal 1 determines whether there is a mobileterminal in the neighborhood and it is the previously registered mobileterminal, and switches the process. If so, the process advances to stepS204. If not, the process proceeds to step S205.

At step S204, the mobile terminal 1 unlocks the previously registeredmobile terminal 2 through the short-range wireless communications. Forexample, the mobile terminal 1 transmits a signal for instructing themobile terminal 2 to be unlocked thereto. Here, the mobile terminals 1and 2 are supposed to be previously registered mutually by the sameuser.

At step S205, the mobile terminal 1 confirms whether to be instructed tobe locked by the user. If so, the process proceeds to step S207. At stepS206, the mobile terminal 1 further confirms whether not to be operatedfor a given length of time. If not, the process proceeds to step S207.If so, the process returns to step S205.

At step S207, the mobile terminal 1 locks the previously registeredmobile terminal 2 through the short-range wireless communications. Forexample, the mobile terminal 1 transmits a signal for instructing themobile terminal 2 to be locked thereto.

At step S208, the mobile terminal 1 is locked.

FIG. 3 is a flowchart illustrating operations for locking and unlockingthe mobile terminal 2 according to the first embodiment.

First, at step S301, the mobile terminal 2 confirms whether to beunlocked when the user enters a password. If so, the process proceeds tostep S303. At step S302, the mobile terminal 2 further confirms whetherto be unlocked through the short-range wireless communications. If so,the process proceeds to step S305. If not, the process returns to stepS301.

At step S303, the mobile terminal 2 confirms whether to be instructed tobe locked by the user. If so, the process proceeds to step S307. At stepS304, the mobile terminal 2 further confirms whether not to be operatedfor a given length of time. If not, the process proceeds to step S307.If so, the process returns to step S303.

At step S305, the mobile terminal 2 confirms whether to be out of thecommunication range of the short-range wireless communications with themobile terminal 1.

If so, the process proceeds to step S307. At step S306, the mobileterminal 2 further confirms whether to be instructed to be locked by themobile terminal 1 through the short-range wireless communications. Ifso, the process proceeds to step S307. If not, the process returns tostep S305.

At step S307, the mobile terminal 2 is locked.

In addition, the mobile terminal I may detect that the short-rangewireless communications established with the mobile terminal 2 isbroken, and transmit a signal for instructing the mobile terminal 2 tobe locked thereto immediately before the communication is broken.

In the first embodiment of the present invention, a plurality of mobileterminals are previously registered mutually through the aboveconfiguration. When one mobile terminal is unlocked among them, anothermobile terminal is unlocked in the communication range of theshort-range wireless communications. When out of the communicationrange, the another mobile terminal can be locked again.

In the present embodiment, an example where two mobile terminals arelocked and unlocked is described; similarly, three or more mobileterminals can be further locked and unlocked.

Second Embodiment

FIG. 4 is a flowchart illustrating operations for locking and unlockingthe mobile terminal 1 according to a second embodiment of the presentinvention. The mobile terminal has the same configuration as that of thefirst embodiment, and therefore descriptions will not be repeated here.

First, at step S401, the mobile terminal 1 confirms whether to beunlocked when the user enters a password. If so, the process proceeds tostep S403. At step S402, the mobile terminal 1 further confirms whetherto be unlocked through the short-range wireless communications. If so,the process proceeds to step S409.

Steps S403 to S408 are the same as steps S202 to S207 of FIG. 2, andtherefore descriptions will not be repeated here.

At step S409, the mobile terminal 1 confirms whether to be out of thecommunication range of the short-range wireless communications with themobile terminal 2.

If so, the process proceeds to step S411. At step S410, the mobileterminal 1 further confirms whether to be instructed to be lockedthrough the short-range wireless communications. If so, the processproceeds to step S411. If not, the process returns to step S409.

At step S411, the mobile terminal 1 is locked.

FIG. 5 is a flowchart illustrating operations for locking and unlockingthe mobile terminal 2 according to the second embodiment.

First, at step S501, the mobile terminal 2 confirms whether to beunlocked when the user enters a password. If so, the process proceeds tostep S503. At step S502, the mobile terminal 2 further confirms whetherto be unlocked through the short-range wireless communications. If so,the process proceeds to step S509.

Steps S503 and S504 are the same as steps S403 and S404 of FIG. 4, andtherefore descriptions will not be repeated here.

At step S505, the mobile terminal 2 unlocks the previously registeredmobile terminal 1 through the short-range wireless communications.

At step S506, the mobile terminal 2 confirms whether to be instructed tobe locked by the user. If so, the process proceeds to step S508. At stepS507, the mobile terminal 2 further confirms whether not to be operatedfor a given length of time. If not, the process proceeds to step S508.

At step S508, the mobile terminal 2 locks the previously registeredmobile terminal 1 through the short-range wireless communications.

At step S509, the mobile terminal 2 confirms whether to be out of thecommunication range of the short-range wireless communications with themobile terminal 1. If so, the process proceeds to step S511. At stepS510, the mobile terminal 2 further confirms whether to be instructed tobe locked through the short-range wireless communications. If so, theprocess proceeds to step S511. If not, the process returns to step S509.

At step S511, the mobile terminal 2 is locked.

In the second embodiment of the present invention, a plurality of mobileterminals are previously registered mutually through the aboveconfiguration. When one mobile terminal is unlocked among them, anothermobile terminal is unlocked in the communication range of theshort-range wireless communications. When out of the communicationrange, the another mobile terminal can be locked again.

First, any mobile terminal may be unlocked. Even if any mobile terminalis unlocked, another mobile terminal can be unlocked, and therefore themobile terminal of the second embodiment is more convenient than that ofthe first embodiment.

In the present embodiment, an example where two mobile terminals arelocked and unlocked is described; similarly, three or more mobileterminals can be further locked and unlocked.

Third Embodiment

FIG. 6 is a flowchart illustrating operations for locking and unlockingthe mobile terminal 1 according to a third embodiment of the presentinvention. The mobile terminal has the same configuration as that of thefirst embodiment, and therefore descriptions will not be repeated here.

Steps S601 to S604 are the same as steps S401 to S404 of FIG. 4, andtherefore descriptions will not be repeated here.

At step S605, the mobile terminal 1 displays a confirmation screen inwhich the mobile terminal 2 is unlocked. A display example will bedescribed later.

At step S606, the mobile terminal 1 confirms whether the user instructsthe mobile terminal 2 to be unlocked. If so, the process advances tostep S607. If not, the process proceeds to step S608.

Steps S608 to S613 are the same as steps S406 to S411 of FIG. 4, andtherefore descriptions will not be repeated here.

FIG. 7 is a display example illustrating a liquid crystal panel of themobile terminal I at the time of detecting the mobile terminal 2 throughthe short-range wireless communications at step S605 of FIG. 6. Adetection report of the mobile terminal 2, a selection button, andnon-selection button of the unlocking are displayed on the liquidcrystal panel. When detecting the mobile terminal 2 through theshort-range wireless communications, the mobile terminal 1 transits toan unlocking selection mode. On the liquid crystal panel 73, anunlocking selection button 74 and an unlocking non-selection button 76are displayed. When the user pushes a push-button switch 75corresponding to the unlocking selection button 74, the mobile terminal2 is unlocked. When the user pushes a push-button switch 77corresponding to the unlocking non-selection button 76, the mobileterminal 1 releases the unlocking selection mode and returns to a normalmode.

In the third embodiment of the present invention, a plurality of mobileterminals are previously registered mutually through the aboveconfiguration. When one mobile terminal is unlocked among them, anothermobile terminal is unlocked in the communication range of theshort-range wireless communications. When out of the communicationrange, the another mobile terminal can be locked again.

Further, upon detection of another mobile terminal, the user can selectwhether to unlock it.

Fourth Embodiment

FIG. 8 is a flowchart illustrating operations for locking and unlockingthe mobile terminal 1 according to a fourth embodiment of the presentinvention. The mobile terminal has the same configuration as that of thefirst embodiment, and therefore descriptions will not be repeated here.

First, at step S801, the mobile terminal 1 searches mobile terminals inthe neighborhood through the short-range wireless communications.

At step S802, the mobile terminal 1 determines whether there is a mobileterminal in the neighborhood and it is the previously registered mobileterminal, and switches the process. If so, the process advances to stepS803. If not, the process proceeds to step S805.

At step S803, the mobile terminal 1 requests the user to enter a simplepassword, and continues to wait until it is correctly entered at stepS804. When the simple password is entered, the process proceeds to stepS807.

At step S805, the mobile terminal 1 requests the user to enter acomplicated password, and continues to wait until it is correctlyentered at step S806. When the complicated password is entered, theprocess proceeds to step S807.

The simple password is, for example, a three-character number, and thecomplicated password is, for example, a ten-character number. That is,strengths of both passwords are different from each other.

At step S807, the mobile terminal 1 is unlocked. Here, the mobileterminals 1 and 2 are supposed to be previously registered mutually bythe same user.

At step S808, the mobile terminal 1 confirms whether to be instructed tobe locked by the user. If so, the process proceeds to step S810. At stepS809, the mobile terminal 1 further confirms whether not to be operatedfor a given length of time. If not, the process proceeds to step S810.

At step S810, the mobile terminal 1 is locked.

Operations for locking and unlocking the mobile terminal 2 are the sameas those of the mobile terminal 1.

In the fourth embodiment of the present invention, a plurality of mobileterminals are previously registered mutually through the aboveconfiguration. When both mobile terminals are in the communication rangeof the short-range wireless communications, an authentication level forunlocking the mobile terminal is simplified. When both the mobileterminals are out of the communication range of the short-range wirelesscommunications, an authentication level for unlocking the mobileterminal is detailed. Therefore, as compared to a case of simply fixingthe authentication level, safety is high. On the other hand, as comparedto a case of fixing the authentication level in detail, usability ispreferable.

In the present embodiment, an example where the number of characters ofthe password is changed is described as switching of the authenticationlevel. Further, there may be changed a principal matching rate ofbiometrics authentication such as face and finger authentication types,or a character matching rate of character authentication.

In the present embodiment, an example where two mobile terminals arelocked and unlocked is described; similarly, three or more mobileterminals can be further locked and unlocked.

Fifth Embodiment

FIG. 9 is a flowchart illustrating operations for locking and unlockingthe mobile terminal 1 according to a fifth embodiment of the presentinvention. The mobile terminal has the same configuration as that of thefirst embodiment, and therefore descriptions will not be repeated here.

First, at step S901, the mobile terminal 1 searches mobile terminals inthe neighborhood through the short-range wireless communications.

At step S902, the mobile terminal 1 determines whether there is a mobileterminal in the neighborhood and it is the previously registered mobileterminal, and switches the process. If so, the process proceeds to stepS903. If not, the process returns to step S901.

At step S903, the mobile terminal 1 is unlocked. Here, the mobileterminals 1 and 2 are supposed to be previously registered mutually bythe same user.

At step S904, the mobile terminal 1 confirms whether to be out of thecommunication range of the short-range wireless communications with themobile terminal 2. The mobile terminal 1 continues to wait until out ofthe communication range. When the mobile terminal 1 is out of thecommunication range, the process proceeds to step S905.

At step S905, the mobile terminal 1 is locked.

Operations for locking and unlocking the mobile terminal 2 are the sameas those of the mobile terminal 1.

In the fifth embodiment of the present invention, a plurality of mobileterminals are previously registered mutually through the aboveconfiguration. When in the communication range of the short-rangewireless communications, they are mutually unlocked. When out of thecommunication range, they are locked again. Therefore, the mobileterminal of the present embodiment is more convenient than those of thefirst and second embodiments.

In the present embodiment, an example where two mobile terminals arelocked and unlocked is described; similarly, three or more mobileterminals can be further locked and unlocked.

Sixth Embodiment

FIG. 10 is a flowchart illustrating a warning operation of the mobileterminal 1 according to a sixth embodiment of the present invention. Themobile terminal has the same configuration as that of the firstembodiment, and therefore descriptions will not be repeated here.

First, at step S1001, the mobile terminal 1 searches mobile terminals inthe neighborhood through the short-range wireless communications.

At step S1002, the mobile terminal I determines whether there is amobile terminal in the neighborhood and it is the previously registeredmobile terminal, and switches the process. If so, the process proceedsto step SI003. If not, the process returns to step S1001.

At step S1003, the mobile terminal 1 confirms whether to be out of thecommunication range of the short-range wireless communications with themobile terminal 2.

If so, the process proceeds to step S1004. If not, the process returnsto step S1003.

At step S1004, the mobile terminal 1 gives warning to the user throughsounds or vibrations. Alternatively, the mobile terminal 1 sends a mailto another mobile terminal. At this time, when having a GPS (GlobalPosition System) function, the mobile terminal I may transmit positionalinformation to the another mobile terminal.

The warning operation of the mobile terminal 2 is the same as that ofthe mobile terminal 1.

In the sixth embodiment of the present invention, a plurality of mobileterminals are previously registered mutually through the aboveconfiguration. In the case where they are once in the communicationrange of the short-range wireless communications, upon being out of thecommunication range next, the mobile terminal I notifies the user ofthat effect, thereby preventing the mobile terminals from being lost.

Suppose, for example, that the present embodiment is combined with thefirst embodiment. In this case, the mobile terminal 2 can notify theuser that the mobile terminal 2 is locked because of moving to theoutside of the communication range of the short-range wirelesscommunications with the mobile terminal 1.

In the present embodiment, an example where two mobile terminals performa warning operation is described; similarly, three or more mobileterminals can further perform a warning operation.

In addition, the above-described embodiments are described in detail inorder to clearly describe the present invention, and are not necessarilylimited to the mobile terminal having all the described constructions.Further, a part of configurations according to one embodiment can bereplaced by those according to other embodiments, and the configurationsaccording to other embodiments can be added to that according to oneembodiment. Further, an addition, deletion, or replacement of theconfigurations according to other embodiments can be performed by usinga part of the configurations according to each embodiment.

A part or all of the respective structures, functions, processing units,and processing approaches may be realized by hardware by designingthrough the integrated circuit, for example. Those structures, functionsand the like may be realized by software by interpreting and executingthe program for realizing the respective functions through a processor.Information with respect to the program, table, and file for realizingthe respective functions may be stored in the recording unit such as thememory, hard disk, and SSD (Solid State Drive), or the recording mediumsuch as the IC card and SD card.

The examples show the control line and information line considered asnecessary for the explanation, which does not necessarily show all thecontrol lines and information lines of the product. Actually, almost allthe components may be considered to be connected with one another.

It should be further understood by those skilled in the art thatalthough the foregoing description has been made on embodiments of theinvention, the invention is not limited thereto and various changes andmodifications may be made without departing from the spirit of theinvention and the scope of the appended claims.

1. (canceled)
 2. A mobile terminal, comprising: a transceiver whichperforms short-range wireless communications; a memory which storesinformation about an another mobile terminal; and a controller whichswitches a mobile terminal between an unlocked state and a locked statebased on an authentication input to the mobile terminal; wherein, whenconditions are met, the controller controls the mobile terminal totransmit information to the another mobile terminal for switching astate of the another mobile terminal from a locked state to an unlockedstate; wherein the conditions include: first, the mobile terminal is inthe locked state, the another mobile terminal is in the locked state,and the another mobile terminal is within communication range of theshort-range wireless communications of the transceiver; second, afterthe mobile terminal is in the locked state, the another mobile terminalis in the locked state, and the another mobile terminal is withincommunication range of the short-range wireless communications of thetransceiver, performing via the transceiver, the short-range wirelesscommunications with the another mobile terminal; and third, after theperforming, receiving, by the controller, the authentication input forswitching the mobile terminal from the locked state to the unlockedstate; and wherein the controller controls the mobile terminal totransmit information to the another mobile terminal for switching thestate of the another mobile terminal from the unlocked state to thelocked state based on the short-range wireless communication beingbroken.
 3. The mobile terminal according to claim 2, wherein theshort-range wireless communication is broken when a distance between themobile terminal and the another mobile terminal is outside a rangerequired to maintain the short-range wireless communication.
 4. Themobile terminal according to claim 2, wherein the authentication inputis a biometrics authentication.
 5. The mobile terminal according toclaim 4, wherein the biometrics authentication includes at least one ofa face authentication or a finger authentication.
 6. The mobile terminalaccording to claim 2, wherein before unlocking the another mobileterminal, the mobile terminal requests confirmation.
 7. The mobileterminal according to claim 2, further configured to store informationabout two or more another mobile terminals in the memory.
 8. The mobileterminal according to claim 2, wherein the short-range wirelesscommunication is via a Bluetooth connection.
 9. The mobile terminalaccording to claim 2, wherein the short-range wireless communication isvia an infrared connection or a Wi-Fi connection.
 10. The mobileterminal according to claim 2, wherein the mobile terminal is a mobilephone.
 11. The mobile terminal according to claim 2, wherein thecontroller switches the state of the mobile terminal from the unlockedstate to the locked state if the controller does not receive anoperation for a given length of time.
 12. The mobile terminal accordingto claim 2, wherein the controller outputs a confirmation on a displayof the mobile terminal before transmitting the information for switchingthe state of the another mobile terminal from the locked state to theunlocked state.
 13. The mobile terminal according to claim 2, whereinthe controller issues a warning when the short-range wirelesscommunication is broken.
 14. The mobile terminal according to claim 13,wherein the warning includes at least one of sound, vibration andE-mail.
 15. A method for controlling a mobile terminal, comprising thesteps of: performing short-range wireless communications; storinginformation about an another mobile terminal in a memory; receiving anauthentication input to the mobile terminal; switching a state of themobile terminal from a locked state to an unlocked state based on theauthentication input; and transmitting information from the mobileterminal to the another mobile terminal for switching a state of theanother terminal from a locked state to an unlocked state whenconditions are met; wherein the conditions include: first, the mobileterminal is in the locked state, the another mobile terminal is in thelocked state, and the another mobile terminal is in communication rangeof the short-range wireless communications; second, after the mobileterminal is in the locked state, the another mobile terminal is in thelocked state, and the another mobile terminal is within communicationrange of the short-range wireless communications, performing, via themobile terminal, the short-range wireless communication with the anothermobile terminal; and third, after the performing, receiving theauthentication input by the mobile terminal for switching the mobileterminal from the locked state to the unlocked state; and transmittinginformation from the mobile terminal to the another mobile terminalwhich is for switching the state of the another mobile terminal from thelocked state to the unlocked state based on the short-range wirelesscommunication being broken.
 16. The method for controlling the mobileterminal according to claim 15, wherein the short-range wirelesscommunication is broken when a distance between the mobile terminal andthe another mobile terminal is outside a range required to maintain theshort-range wireless communication.
 17. The method for controlling themobile terminal according to claim 15, wherein the authentication inputis a biometrics authentication.
 18. The method for controlling themobile terminal according to claim 17, wherein the biometricsauthentication includes a face authentication and a fingerauthentication.
 19. The method for controlling the mobile terminalaccording to claim 15, further comprising requesting confirmation beforeunlocking the another mobile terminal.
 20. The method for controllingthe mobile terminal according to claim 15, wherein the storedinformation in the memory relates to two or more another mobileterminals.
 21. The method for controlling the mobile terminal accordingto claim 15, wherein the short-range wireless communication is via aBluetooth connection.
 22. The method for controlling the mobile terminalaccording to claim 15, wherein the short-range wireless communication isvia an infrared connection or a Wi-Fi connection.
 23. The method forcontrolling the mobile terminal according to claim 15, wherein themobile terminal is a mobile phone.
 24. The method for controlling themobile terminal according to claim 15, further comprising switching thestate of the mobile terminal from the unlocked state to the locked stateif not receiving an operation to the mobile terminal for a given lengthof time.
 25. The method for controlling the mobile terminal according toclaim 15, further comprising outputting a confirmation on a display ofthe mobile terminal before transmitting the information for switchingthe state of the another mobile terminal from the locked state to theunlocked state.
 26. The method for controlling the mobile terminalaccording to claim 15, further comprising issuing a warning when theshort-range wireless communication is broken.
 27. The method forcontrolling the mobile terminal according to claim 26, wherein thewarning includes at least one of a sound, a vibration, and an e-mail.28. A lock state control system comprising: a first mobile terminal anda second mobile terminal, wherein the first mobile terminal comprises atransceiver which performs short-range wireless communications, a memorywhich stores information about the second mobile terminal, and acontroller which switches the first mobile terminal between an unlockedstate and a locked state based on an authentication input to the firstmobile terminal from a user; wherein, when conditions are met, thecontroller controls the first mobile terminal to transmit information tothe second mobile terminal for switching a state of the second mobileterminal from a locked state to an unlocked state; wherein theconditions include: first, the first mobile terminal is in the lockedstate, the second mobile terminal is in the locked state, and the secondmobile terminal is in communication range of the short-range wirelesscommunications of the first mobile terminal; second, after the firstmobile terminal is in the locked state, the second mobile terminal is inthe locked state, and the second mobile terminal is in communicationrange of the short-range wireless communications of the first mobileterminal, performing, via the first mobile terminal, the short-rangewireless communications with the second mobile terminal; and third,after the performing, receiving via the first mobile terminal, theauthentication input for switching a state of the first mobile terminalfrom a locked state to an unlocked state; and wherein the controllercontrols the mobile terminal to transmit information to the anothermobile terminal for switching the state of the another mobile terminalfrom the unlocked state to the locked state based on the short-rangewireless communication being broken.
 29. The lock state control systemaccording to claim 28, wherein the short-range wireless communication isbroken when a distance between the first mobile terminal and the secondmobile terminal is outside a range required to maintain the short-rangewireless communication.
 30. The lock state control system according toclaim 28, wherein the authentication input is a biometricsauthentication.
 31. The lock state control system according to claim 29,wherein the biometrics authentication includes at least one of a faceauthentication and a finger authentication.
 32. The lock state controlsystem according to claim 28, wherein before unlocking the second mobileterminal, the first mobile terminal requests confirmation.
 33. The lockstate control system according to claim 28, wherein the first mobileterminal further configured to store information about two or more thesecond mobile terminals in the memory.
 34. The lock state control systemaccording to claim 28, wherein the short-range wireless communication isvia a Bluetooth connection.
 35. The lock state control system accordingto claim 28, wherein the short-range wireless communication is via aninfrared connection or a Wi-Fi connection.
 36. The lock state controlsystem according to claim 28, wherein the first mobile terminal is amobile phone.
 37. The lock state control system according to claim 28,wherein the second mobile terminal is a mobile phone.
 38. The lock statecontrol system according to claim 28, wherein the controller switchesthe state of the first mobile terminal from the unlocked state to thelocked state if the controller does not receive an operation for a givenlength of time.
 39. The lock state control system according to claim 28,wherein a controller of the second mobile terminal switches the state ofthe second mobile terminal from the unlocked state to the locked stateif the controller of the second mobile terminal does not receive anoperation for a given length of time.
 40. The lock state control systemaccording to claim 28, wherein the controller outputs a confirmation ona display of the first mobile terminal before transmitting theinformation for switching the state of the second mobile terminal fromthe locked state to the unlocked state.
 41. The lock state controlsystem according to claim 28, wherein the controller issues a warningwhen the short-range wireless communication is broken.
 42. The lockstate control system according to claim 41, wherein the warning includesat least one of a sound, a vibration, and an e-mail.
 43. The lock statecontrol system according to claim 28, wherein a controller of the secondmobile terminal issues a warning when the short-range wirelesscommunication is broken.
 44. The lock state control system according toclaim 43, wherein the warning includes at least one of a sound, avibration, and an e-mail.
 45. A lock state control system comprising: afirst mobile terminal and a second mobile terminal, wherein the firstmobile terminal comprises a transceiver which performs short-rangewireless communications, a memory which stores information about thesecond mobile terminal, and a controller which switches the first mobileterminal between an unlocked state and a locked state based on anauthentication input to the first mobile terminal from a user; wherein,when conditions are met, the controller controls the first mobileterminal to transmit information to the second mobile terminal forswitching a state of the second mobile terminal from a locked state toan unlocked state; wherein the conditions include: first, the firstmobile terminal is in the locked state, the second mobile terminal is inthe locked state, and the second mobile terminal is in communicationrange of the short-range wireless communications of the first mobileterminal; second, after the first mobile terminal is in the lockedstate, the second mobile terminal is in the locked state, and the secondmobile terminal is in communication range of the short-range wirelesscommunications of the first mobile terminal, performing, via the firstmobile terminal, the short-range wireless communications with the secondmobile terminal; and third, after the performing, receiving via thefirst mobile terminal, the authentication input for switching a state ofthe first mobile terminal from a locked state to an unlocked state; andwherein a controller of the second mobile terminal switches a state ofthe second mobile terminal from the unlocked state to the locked statewhen the second mobile terminal come out from the communication range ofthe short-range wireless communications of the first mobile terminal.46. The lock state control system according to claim 45, wherein theauthentication input is a biometrics authentication.
 47. The lock statecontrol system according to claim 46, wherein the biometricsauthentication includes at least one of a face authentication and afinger authentication.
 48. The lock state control system according toclaim 45, wherein before unlocking the second mobile terminal, the firstmobile terminal requests confirmation.
 49. The lock state control systemaccording to claim 45, wherein the first mobile terminal furtherconfigured to store information about two or more the second mobileterminals.
 50. The lock state control system according to claim 45,wherein the short-range wireless communication is via a Bluetoothconnection.
 51. The lock state control system according to claim 45,wherein the short-range wireless communication is via an infraredconnection or a Wi-Fi connection.
 52. The lock state control systemaccording to claim 45, wherein the first mobile terminal is a mobilephone.
 53. The lock state control system according to claim 45, whereinthe second mobile terminal is a mobile phone.
 54. The lock state controlsystem according to claim 45, wherein the controller switches the stateof the first mobile terminal from the unlocked state to the locked stateif the controller does not receive an operation for a given length oftime.
 55. The lock state control system according to claim 45, wherein acontroller of the second mobile terminal switches the state of thesecond mobile terminal from the unlocked state to the locked state ifthe controller of the second mobile terminal does not receive anoperation for a given length of time.
 56. The lock state control systemaccording to claim 45, wherein the controller outputs a confirmation ona display of the first mobile terminal before transmitting theinformation for switching the state of the second mobile terminal fromthe locked state to unlocked state.
 57. The lock state control systemaccording to claim 45, wherein the controller issues a warning when theshort-range wireless communication is broken.
 58. The lock state controlsystem according to claim 57, wherein the warning includes at least oneof a sound, a vibration, and an e-mail.
 59. The lock state controlsystem according to claim 45, wherein a controller of the second mobileterminal issues a warning when the short-range wireless communication isbroken.
 60. The lock state control system according to claim 59, whereinthe warning includes at least one of a sound, a vibration, and ane-mail.